a) Field of the Invention
This invention relates to wireless base stations.
b) Related Prior Art
Wireless base stations are a recent development and are provided for the purpose of connecting cordless wireless telephone handsets into telecommunications circuits. For this purpose, the base stations comprise radio transmitters and receivers which are connected into the circuits, these transmitters and receivers being compatible with transmitters and receivers in the handsets for the transmission and reception of messages to and from the handsets within a certain limited operational distance. Base stations for use inside buildings meet requirements which are less stringent environmentally than those for use in the outside environment. Base stations for use outside buildings ideally need to be designed to withstand certain weather conditions. In the event of outside base stations being subjected to extremes of cold, heat or direct sunlight, it may be presupposed that suitable heating and/or cooling equipment should be included in the base o stations, such equipment being operable, as the case may warrant, to maintain suitable temperatures for the equipment of the base stations. However, such heating or cooling equipment would require a power supply. In the event that the power supply to such equipment failed then this would undoubtedly result in destruction of most or all of the equipment within a base station. As telephone equipment is specifically designed for many long years of use and such requirements also desirably extend to the design of wireless base stations, it would be overly optimistic to expect heating or cooling equipment to be operable without breakdown for such extended periods. As a result it can only be expected that a majority of base stations would breakdown and need replacement or major repair upon failure of installed heating or cooling equipment. Such failures could occur a long time before the end of the expected useful life of the base stations. As may be seen, therefore, the use of cooling and/or heating equipment in outdoor base stations could not be expected to provide a commercially useful article and undue replacement expense, maintenance costs and inconvenience in sudden breakdown of apparatus would result.
In order to avoid the use of heating and cooling equipment in outdoor base stations, restrictions have necessarily been placed upon their location in an attempt to minimize the adverse weather conditions. For instance outside base stations have been located in positions where maximum shadow can be achieved against the effects of direct sunlight, especially in hot temperature zones. Protective overhangs have been useful for this purpose and have also combated, to a degree, against extreme cold or wind conditions. As may be seen, this heavily restricts the choice of sites for locations of base stations and in some cases, it may be extremely difficult to find a suitable location for a base station.